The present disclosure relates to a liquid crystal photo alignment agent, and a method of manufacturing liquid crystal display using the same.
Generally, liquid crystal displays are divided into twisted nematic liquid crystal display, in-plane electric field type liquid crystal display, or vertical alignment liquid crystal display depending on properties of liquid crystal layers. In particular, in liquid crystal display, liquid crystals disposed between electrodes need to be aligned in a certain direction. As a method for aligning liquid crystal molecules in a certain direction, the rubbing method and the photo alignment method are available.
Limitations in the rubbing method such as generation of foreign substances and lack of uniformity of alignment may be relaxed using the photo alignment method. Examples of materials used in the photo alignment method include polymers containing photofunctional groups such as azobenzene, cumarine, imide, chalcone, and cinnamate. In such polymers, reactions such as photoisomerization, photocrosslinking, and photodegradation anisotropically occur due to polarized light irradiation. Through this, anisotropy is generated on the surfaces of the polymers, so that liquid crystals are aligned in one direction.
Liquid crystal photo alignment agents used in the photo alignment method should have a good coating property to substrates. Also, when the liquid crystal photo alignment agent is applied to a display, the agent should relax residual image limitation in terms of reliability.